[PATCH] drm/xe/display: Make display suspend/resume work on discrete

[Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>]

We should unpin before evicting all memory, and repin after GT resume.
This way, we preserve the contents of the framebuffers, and won't hang
on resume due to migration engine not being restored yet.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: stable@xxxxxxxxxxxxxxx # v6.8+
Reviewed-by: Uma Shankar <uma.shankar@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20240806105044.596842-3-maarten.lankhorst@xxxxxxxxxxxxxxx
Signed-off-by: Maarten Lankhorst,,, <maarten.lankhorst@xxxxxxxxxxxxxxx>
(cherry picked from commit cb8f81c1753187995b7a43e79c12959f14eb32d3)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>

diff --git a/drivers/gpu/drm/xe/display/xe_display.c b/drivers/gpu/drm/xe/display/xe_display.c
index ca4468c82078..49de4e4f8a75 100644
--- a/drivers/gpu/drm/xe/display/xe_display.c
+++ b/drivers/gpu/drm/xe/display/xe_display.c
@@ -283,6 +283,27 @@ static bool suspend_to_idle(void)
 	return false;
 }
 
+static void xe_display_flush_cleanup_work(struct xe_device *xe)
+{
+	struct intel_crtc *crtc;
+
+	for_each_intel_crtc(&xe->drm, crtc) {
+		struct drm_crtc_commit *commit;
+
+		spin_lock(&crtc->base.commit_lock);
+		commit = list_first_entry_or_null(&crtc->base.commit_list,
+						  struct drm_crtc_commit, commit_entry);
+		if (commit)
+			drm_crtc_commit_get(commit);
+		spin_unlock(&crtc->base.commit_lock);
+
+		if (commit) {
+			wait_for_completion(&commit->cleanup_done);
+			drm_crtc_commit_put(commit);
+		}
+	}
+}
+
 void xe_display_pm_suspend(struct xe_device *xe, bool runtime)
 {
 	bool s2idle = suspend_to_idle();
@@ -300,6 +321,8 @@ void xe_display_pm_suspend(struct xe_device *xe, bool runtime)
 	if (!runtime)
 		intel_display_driver_suspend(xe);
 
+	xe_display_flush_cleanup_work(xe);
+
 	intel_dp_mst_suspend(xe);
 
 	intel_hpd_cancel_work(xe);
diff --git a/drivers/gpu/drm/xe/xe_pm.c b/drivers/gpu/drm/xe/xe_pm.c
index de3b5df65e48..9a3f618d22dc 100644
--- a/drivers/gpu/drm/xe/xe_pm.c
+++ b/drivers/gpu/drm/xe/xe_pm.c
@@ -91,13 +91,13 @@ int xe_pm_suspend(struct xe_device *xe)
 	for_each_gt(gt, xe, id)
 		xe_gt_suspend_prepare(gt);
 
+	xe_display_pm_suspend(xe, false);
+
 	/* FIXME: Super racey... */
 	err = xe_bo_evict_all(xe);
 	if (err)
 		goto err;
 
-	xe_display_pm_suspend(xe, false);
-
 	for_each_gt(gt, xe, id) {
 		err = xe_gt_suspend(gt);
 		if (err) {
@@ -151,11 +151,11 @@ int xe_pm_resume(struct xe_device *xe)
 
 	xe_irq_resume(xe);
 
-	xe_display_pm_resume(xe, false);
-
 	for_each_gt(gt, xe, id)
 		xe_gt_resume(gt);
 
+	xe_display_pm_resume(xe, false);
+
 	err = xe_bo_restore_user(xe);
 	if (err)
 		goto err;
@@ -363,10 +363,11 @@ int xe_pm_runtime_suspend(struct xe_device *xe)
 	mutex_unlock(&xe->mem_access.vram_userfault.lock);
 
 	if (xe->d3cold.allowed) {
+		xe_display_pm_suspend(xe, true);
+
 		err = xe_bo_evict_all(xe);
 		if (err)
 			goto out;
-		xe_display_pm_suspend(xe, true);
 	}
 
 	for_each_gt(gt, xe, id) {